The present invention is related generally to web handling apparatus and more particularly, to the collecting and removing of web trim.
Some printers and document handling systems use one or more tractor feeders to move a continuous paper web. In the tractor feeders, sprockets are generally use to drive strips at the outer edges of a paper web. The strips are often trimmed or stripped away in a post-processing step. These paper strips, or web trim, are thrown out or recycled. In the stripping processing, paper dust is usually generated as the strips are trimmed. The web trim and paper dust must be somehow collected and discarded.
U.S. Pat. No. 5,322,232 (Freeman et al.) discloses a trim removal system, wherein the trim is collected in a receiving funnel and moved into a collection drum by vacuum fans. The web trim is wound into a bale and paper dust is trapped in a dust trap for disposal. While the bale could simplify the disposal of the web trim, the remove system must be equipped with a rewinding mechanism for winding the bale. This increases the complexity of the design and the manufacturing and maintenance costs. Furthermore, when the bale is removed from the trim removal system, the rewinding mechanism must be stopped.
Thus, it is advantageous and desirable to provide a trim removal system with a simplified design, wherein the collected trim can be removed from the system while the system continues the trim collection operation.
It is a primary object of the present invention to provide a web trim collection system, wherein the trim can be collected without interruption even when the collected trim is removed from the system for disposal. This object can be achieved by using a collection bin to collect the trim under normal operation, and a divert bin to receive the trim when the collection bin is removed from the collection system for changeovers of the collection bin.
According to the first aspect of the present invention, a web trim collection system connected to a trim receiver which receives web trim, said system comprising:
a channel having a first end and a second end, the first end communicating with the trim receiver;
a divert bin having an inlet in communication with the second end of the channel, wherein the divert bin further has a collection region, an aperture, and means for operating the divert bin between a first position and a second position,
a collection bin having an inlet communicable with the aperture of the divert bin when the divert bin is operated in a first position so as to allow the web trim to pass through the divert bin and to be deposited into the collection bin, and when the divert bin is operated in the second position, the collection region of the divert bin collects the web trim received through the receiving end of the divert bin, thereby preventing the web trim from being deposited into the collection bin and allowing the collection bin to be removed from said web trim collection system for changeovers of the collection bin while said collection system continues to collect web trim; and
a trim moving mechanism for moving the web trim from the trim receiver into the divert bin or further into the collection bin.
Preferably, when the divert bin is operated in the first position, the collection region is so positioned that the web trim collected in the collection region can be deposited into the inlet of the collection bin through the aperture of the divert bin.
Preferably, the trim moving mechanism comprises an air pressure system for creating an air flow from the trim receiver through the channel, wherein the air pressure system can be one or more blowing fans or vacuum/motor units.
Preferably, the web collection system comprises a sensing mechanism to sense the level of the web trim deposited in the collection bin when the divert bin is operated in the first position, and the system further comprises a warning device which is turned on when the sensing mechanism senses that the level of the web trim deposited in the collection bin has reached a predetermined level. Preferably, the sensing mechanism is capable of causing the system to shut down when the collection bin is filled.
According to the present invention, the web trim collection system comprises one or more air outlets for discharging air brought in by the air flow from the trim collection system into an area surrounding the web trim collection system through one or more air filters.
According to the present invention, the web trim collection system comprises one or more flapper doors communicable with the air outlets and the collection bin for allowing the air in the collection bin to be discharged from the air outlet through the trapper doors when the divert bin is operated in the first position, wherein the trapper doors are closed when the divert bin is operated in the second position so as to prevent the air in the collection bin from entering the air outlets.
According to the present invention, the collection system can be manually turned on or off using a control switch on the collection system or remotely turned on or off by an external device or console through an interface.
According to the present invention, the collection system comprises a platform having a seal, wherein the platform can be operated in a first platform position in contact with the collection bin so as to provide an air seal to the collection bin with the seal when the divert bin is operated in the first position, and the platform can be operated in a second platform position separate from the collection bin so as to allow the collection bin to be removed from the web trim collection system. The collection system further comprises a sensing mechanism to sense the position of the divert bin so as to prevent the platform to be operated in the second platform position when the divert bin is operated in the first position.
According to the present invention, a control lever is used for manually changing the operating position of the divert bin.
The present invention will become apparent upon reading the description taken in conjunction with FIGS. 1 to 5.